import random
from django.conf import settings
from django.db import models
from django.utils import timezone
from django.utils.text import slugify
from django.utils.translation import gettext_lazy as _
from apps.profiles.models import Institution


class CampaignCategory(models.TextChoices):
    MOSQUE_CONSTRUCTION = 'mosque_construction', _('Mosque & Center Construction / Renovation')
    HUMANITARIAN_RELIEF = 'humanitarian_relief', _('Humanitarian & Disaster Relief')
    PILGRIM_SUPPORT = 'pilgrim_support', _('Imam Reza (AS) Pilgrim Services')
    CULTURAL_PUBLICATIONS = 'cultural_publications', _('Quran & Islamic Publications Translation')
    EDUCATIONAL_SCHOLARSHIPS = 'educational_scholarships', _('Seminary & Academic Scholarships')
    GENERAL = 'general', _('General Waqf & Endowment')


class CampaignPriority(models.TextChoices):
    URGENT = 'urgent', _('Urgent Appeal')
    HIGH = 'high', _('High Priority')
    MEDIUM = 'medium', _('Medium Priority')


class PaymentStatus(models.TextChoices):
    COMPLETED = 'completed', _('Completed')
    PENDING = 'pending', _('Pending')
    FAILED = 'failed', _('Failed')


class DonationCampaign(models.Model):
    title = models.CharField(max_length=255, verbose_name=_('Campaign Title'))
    slug = models.SlugField(
        max_length=280,
        unique=True,
        blank=True,
        null=True,
        allow_unicode=True,
        verbose_name=_('Slug / URL Identifier')
    )
    description = models.TextField(verbose_name=_('Campaign Description & Objectives'))
    target_amount = models.DecimalField(
        max_digits=14,
        decimal_places=2,
        verbose_name=_('Target Amount')
    )
    raised_amount = models.DecimalField(
        max_digits=14,
        decimal_places=2,
        default=0.00,
        verbose_name=_('Accumulated Raised Amount')
    )
    currency = models.CharField(
        max_length=10,
        default='USD',
        verbose_name=_('Currency (e.g. USD, EUR, IRR, AED)')
    )
    category = models.CharField(
        max_length=50,
        choices=CampaignCategory.choices,
        default=CampaignCategory.HUMANITARIAN_RELIEF,
        verbose_name=_('Category')
    )
    priority = models.CharField(
        max_length=20,
        choices=CampaignPriority.choices,
        default=CampaignPriority.MEDIUM,
        verbose_name=_('Priority')
    )
    cover_image = models.ImageField(
        upload_to='donations/covers/%Y/%m/',
        blank=True,
        null=True,
        verbose_name=_('Campaign Image')
    )
    institution = models.ForeignKey(
        Institution,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name='donation_campaigns',
        verbose_name=_('Beneficiary Institution / Mosque')
    )
    organization_name = models.CharField(
        max_length=255,
        blank=True,
        null=True,
        verbose_name=_('Managing Foundation Name')
    )
    deadline = models.DateField(
        null=True,
        blank=True,
        verbose_name=_('Campaign Deadline')
    )
    is_active = models.BooleanField(default=True, verbose_name=_('Is Active'))
    is_featured = models.BooleanField(default=False, verbose_name=_('Is Featured'))
    created_at = models.DateTimeField(auto_now_add=True, verbose_name=_('Created At'))
    updated_at = models.DateTimeField(auto_now=True, verbose_name=_('Updated At'))

    class Meta:
        ordering = ('-is_featured', '-priority', '-created_at')
        verbose_name = _('Donation Campaign')
        verbose_name_plural = _('Donation Campaigns')

    def __str__(self):
        return f"{self.title} ({self.raised_amount}/{self.target_amount} {self.currency})"

    def save(self, *args, **kwargs):
        if not self.slug:
            base_slug = slugify(self.title, allow_unicode=True) or f"campaign-{random.randint(1000, 9999)}"
            slug = base_slug
            counter = 1
            while DonationCampaign.objects.filter(slug=slug).exclude(pk=self.pk).exists():
                slug = f"{base_slug}-{counter}"
                counter += 1
            self.slug = slug
        super().save(*args, **kwargs)

    @property
    def progress_percentage(self) -> int:
        if self.target_amount and self.target_amount > 0:
            pct = int((self.raised_amount / self.target_amount) * 100)
            return min(100, pct)
        return 0

    @property
    def donors_count(self) -> int:
        return self.transactions.filter(payment_status=PaymentStatus.COMPLETED).count()


class DonationTransaction(models.Model):
    transaction_reference = models.CharField(
        max_length=100,
        unique=True,
        blank=True,
        verbose_name=_('Transaction Reference'),
        help_text=_('e.g. DON-RAZAVI-2026-XYZ123')
    )
    campaign = models.ForeignKey(
        DonationCampaign,
        on_delete=models.CASCADE,
        related_name='transactions',
        verbose_name=_('Campaign')
    )
    donor_user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name='donations',
        verbose_name=_('Donor Account')
    )
    donor_name = models.CharField(
        max_length=255,
        default='Anonymous Donor',
        verbose_name=_('Donor Display Name')
    )
    donor_email = models.EmailField(
        blank=True,
        null=True,
        verbose_name=_('Donor Email')
    )
    amount = models.DecimalField(
        max_digits=12,
        decimal_places=2,
        verbose_name=_('Donation Amount')
    )
    currency = models.CharField(
        max_length=10,
        default='USD',
        verbose_name=_('Currency')
    )
    payment_status = models.CharField(
        max_length=20,
        choices=PaymentStatus.choices,
        default=PaymentStatus.COMPLETED,
        verbose_name=_('Payment Status')
    )
    created_at = models.DateTimeField(auto_now_add=True, verbose_name=_('Donated At'))

    class Meta:
        ordering = ('-created_at',)
        verbose_name = _('Donation Transaction')
        verbose_name_plural = _('Donation Transactions')

    def __str__(self):
        return f"{self.transaction_reference} - {self.amount} {self.currency} by {self.donor_name}"

    def save(self, *args, **kwargs):
        if not self.transaction_reference:
            year = timezone.now().year
            rand_code = ''.join(random.choices('ABCDEFGHJKLMNPQRSTUVWXYZ23456789', k=6))
            self.transaction_reference = f"DON-RAZAVI-{year}-{rand_code}"
        super().save(*args, **kwargs)